Summary of Vishay Siliconix’s SiP280x Low-Power Current-Mode Controllers for 10-W to 250-W Power Supplies Feature 1-A Output Drivers, Switching Frequencies up to 1 MHz
Siliconix introduced the SiP280x family of low-power current-mode PWM controllers, offering direct replacements for UCC380x/UCC280x series. These BiCMOS-based devices enhance efficiency in 10W to 250W power supplies through reduced start-up and operating currents, enabling smaller external components. They support frequencies up to 1 MHz, feature automatic soft-start, leading-edge blanking, and hiccup-mode protection, and operate within -40°C to +85°C.
Parts used in the SiP280x Pulse-Width Modulation Controllers:
- SiP2800 controller
- SiP2801 controller
- SiP2802 controller
- SiP2803 controller
- SiP2804 controller
- SiP2805 controller
- SO-8 package
- TSSOP-8 package
Santa Clara, CA (PRWEB) November 4, 2004
A new family of low-power current-mode controllers that provide increased efficiency and flexibility in cost-sensitive power-supply designs was announced today by Siliconix incorporated (NASDAQ: SILI), an 80.4%-owned subsidiary of Vishay Intertechnology, Inc. (NYSE: VSH).
The first true direct replacements for the industry-standard UCC380x and UCC280x families of low-power current-mode controllers, the new SiP280x pulse-width modulation (PWM) controllers serve as versatile, low-cost building blocks for a broad variety of converters in both offline and dc-to-dc current-mode switching power supplies in industrial, fixed telecom, and datacom applications. These devices also are suitable for point of load (POL) regulation; high-efficiency dc-to-dc converter modules; and buck, boost, flyback, and forward converters.
Siliconix’s pin-for-pin-compatible replacements to the UCC380x/UCC280x family include the SiP2800, SiP2801, SiP2802, SiP2803, SiP2804, and SiP2805, each of which is built on a BiCMOS process and available in either a SO-8 or TSSOP-8 package. Intended for 10-W to 250-W power supplies, the new controllers can operate from a supply voltage as low as 5 V.
The SiP280x series provides improved power supply efficiency relative to the older UC384x/UC284x devices by taking advantage of Siliconix’s advanced BiCMOS design and processing. This yields significantly lower start-up and operating current requirements of 100 microamps and 500 microamps respectively. The low start-up current substantially reduces dissipation in any dropping resistors required for start-up of the part, while the minimized operating current drastically cuts the amount of power that must be supplied to a SiP280x controller merely to power the IC. The lower start-up and operating currents additionally allow the SiP280x devices to use smaller external capacitors from the VCC pin to ground.
The BiCMOS process with which these parts are built and their on-chip +/-1-A totem-pole output drivers enable the SiP280x controllers to operate usefully at frequencies up to 1 MHz. This ability for higher-frequency operation allows the use of smaller power inductors and capacitors in many power supply designs.
With an internal soft-start mechanism that is active at power-on and under fault conditions, the SiP280X controllers reduce stress on external components, thereby enhancing power supply performance and reliability. The new ICs also feature built-in leading-edge blanking on the current sense pin. This blanking eliminates the need for external filter components while keeping voltage spikes from triggering the parts’ current comparators, ensuring that the current-regulation loop and the overcurrent limiter circuits function properly.
The SiP280x family’s combination of automatic soft-start and leading-edge blanking simplifies circuit design. As a result, designers are able to optimize power supply performance for normal operating conditions, with reduced component count as compared to previous solutions. At the same time, the ICs provide an automatic and elegant “hiccup-mode” protection (overcurrent shutdown with soft-start retry) feature that protects the supply and its load during severe fault conditions.
The SiP280x series also features a variety of turn-on and turn-off thresholds to accommodate various supply voltage, UVLO, and hysteresis requirements. The controllers are rated for an operating temperature range of -40 to +85 degrees Celsius.
Samples and production quantities of the SiP280x controllers are available now, with lead times of 8 to 12 weeks for larger orders. Pricing for U.S. delivery is $ 1.50 for quantities of 1,000 pieces or more.
Siliconix is a leading manufacturer of power MOSFETs, power ICs, analog switches, and multiplexers for computers, cell phones, fixed communications networks, automobiles, and other consumer and industrial electronic systems. With 2003 worldwide sales of $ 392.1 million, the Company’s facilities include a Class 1 wafer fab dedicated to the manufacture of power products in Santa Clara, California, and an affiliated Class 1 wafer fab located in Itzehoe, Germany. The Company’s products are also fabricated by subcontractors in Japan, Germany, China, Taiwan, and the United States. Assembly and test facilities include a company-owned facility in Taiwan, a joint venture in Shanghai, China, and subcontractors in the Philippines, China, Taiwan, and Israel.
Vishay, a Fortune 1,000 Company listed on the NYSE, is one of the world’s largest manufacturers of discrete semiconductors (diodes, rectifiers, transistors, optoelectronics, and selected ICs) and passive electronic components (resistors, capacitors, inductors, and transducers). The Company’s components can be found in products manufactured in a very broad range of industries worldwide. Vishay is headquartered in Malvern, Pennsylvania, and has plants in 17 countries employing over 27,000 people. Vishay can be found on the Internet at http://www.vishay.com.
# # #
More Electronic Circuit Press Releases
- What are the new SiP280x controllers designed to replace?
The SiP280x controllers serve as direct pin-for-pin replacements for the industry-standard UCC380x and UCC280x families. - Can the SiP280x series operate at high frequencies?
Yes, the BiCMOS process and on-chip output drivers enable operation at frequencies up to 1 MHz. - How does the SiP280x improve power supply efficiency compared to older devices?
It achieves higher efficiency by significantly lowering start-up current to 100 microamps and operating current to 500 microamps. - What internal features simplify circuit design for designers?
The combination of automatic soft-start and leading-edge blanking simplifies design and reduces component count. - Does the SiP280x offer protection during severe fault conditions?
Yes, it provides an automatic hiccup-mode protection feature with overcurrent shutdown and soft-start retry. - What is the operating temperature range for these controllers?
The controllers are rated for an operating temperature range of negative 40 to plus 85 degrees Celsius. - Are the SiP280x controllers available for immediate purchase?
Samples and production quantities are available now, though lead times for larger orders are 8 to 12 weeks. - What packages are the SiP280x controllers available in?
The devices are available in either a SO-8 or TSSOP-8 package.
